gpio: of: Check propname before applying "cs-gpios" quirks

gpio: of: Check propname before applying "cs-gpios" quirks

SPI GPIO device has more than just "cs-gpio" property in its node and
would request those GPIOs as a part of its initialization. To avoid
applying CS-specific quirk to all of them add a check to make sure
that propname is "cs-gpios".

Signed-off-by: Andrey Smirnov <[email protected]>
Cc: Linus Walleij <[email protected]>
Cc: Bartosz Golaszewski <[email protected]>
Cc: Chris Healy <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Linus Walleij <[email protected]>